Table 2.

Multivariate Cox regression analyses for the associations between high RDW and the incidence of mCHS-defined and KCL-defined frailty.

mCHS-defined frailty
Groups	HR	95% CI	p value
Model 1
Low-RDW group	1 (reference)
High-RDW group	1.80	1.25–2.60	0.002
Model 2
Low-RDW group	1 (reference)
High-RDW group	1.62	1.10—2.37	0.015
Model 3
Low-RDW group	1 (reference)
High-RDW group	1.58	1.07–2.32	0.023
KCL-defined frailty
Groups	HR	95% CI	p value
Model 1
Low-RDW group	1 (reference)
High-RDW group	1.64	1.11–2.42	0.012
Model 2
Low-RDW group	1 (reference)
High-RDW group	1.54	1.02–2.34	0.041
Model 3
Low-RDW group	1 (reference)
High-RDW group	1.50	0.98–2.28	0.063

The low- and high-RDW groups were defined as RDW < 13.5% and ≥ 13.5%, respectively.

Model 1: Adjusted for age and sex.

Model 2: Further adjusted for BMI, eGFR, HbA1c, and baseline mCHS or KCL score.

Model 3: Model 2 further adjusted for hemoglobin.

RDW: Red blood cell distribution width, mCHS: Modified version of cardiovascular health study, KCL: Kihon Checklist,　HR: Hazard ratio, CI: Confidence interval, BMI: Body mass index, eGFR: Estimated glomerular filtration rate, HbA1c: Glycohemoglobin.